BirdAnalyst
Species · Iowa · BBS 2025 Release · 1966–2024

Black-billed Cuckoo Population Trend in Iowa

All statesGeneralists

Black-billed Cuckoo in Iowa has fallen sharply: down 75% on the route-weighted index since 1969.

-75%Since 1969
36Routes In State
49Years

Notable Black-billed Cuckoo Trends in Iowa

long arc declinecomputed index

Black-billed Cuckoo has fallen sharply in Iowa: down 75% on the route-weighted index since 1969.

Black-billed Cuckoo Population Forecast in Iowa

If the recent trend holds, Black-billed Cuckoo in Iowa is projected to fall about 29% by 2024 — from 0.08 in 2019 to a central estimate of 0.06 (95% range 0.00–0.55). A 5-year backtest shows a typical error of ±125.6%, with 100% of held-out values landing inside the 95% band.

-29%Change by 2024
0.06Projected 2024 index
0.00–0.5595% range
±125.6%Backtest error
19672024
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected index95% low95% high
20200.100.000.59
20210.090.000.58
20220.080.000.57
20230.070.000.56
20240.060.000.55

Black-billed Cuckoo Survey Routes in Iowa

Routes recording Black-billed Cuckoo in Iowa.
Wales320181977
Washta320031973
Melrose220101978
College Spgs219921968
Cedar Valley219921968
Prairieburg219821972
Zearing219941971
Rock Valley220011970
Mt Hamill120151969
Exline120071985
Bedford120181989
Bryant119921968
West Liberty120171972
Brooklyn120051967
Williamsburg119971967
Red Rock120011970
Desmoines119781978
Panther120091992
Washington120051973
Neola120081968
Maquoketa120191967
Alice119971970
Hudson120061970
Dinsdale120051982
Kanawha120011967

Black-billed Cuckoo Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawaregeorgiaidahoillinoisindianakansaskentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.